Studies on efficient use of water in onion (Allium cepa L.) through drip irrigation under semi-arid conditions

The field experiment was conducted during 2011-12 and 2012-13 during late monsoon at the Department of Horticulture, College of Agriculture, University of Agricultural Sciences, Raichur, Karnataka, India, with the objectives to work out the water requirement of onion cultivar 'N-53' and to compare the performance of drip and furrow irrigation methods with regard to yield, quality, water use efficiency and economics at 60, 80, 100 and 120% evapotranspiration (ET) levels. The experimental plot was a randomized block design (RBD) with four replications. Response of onion through drip irrigation levels in terms of average bulb weight (110.8 g) and yield (28.4 t ha^-1) were significantly higher at 80% ET level. Maximum TSS (13.3 °B) was observed by drip irrigation at 120% ET level which was on par with irrigation at 80% ET level. All drip irrigation treatments resulted in higher benefit to cost ratio (4.1 to 6.0). The water saved using an 80% ET level and drip irrigation could be utilized to irrigate an extra area from which the projected income of Indian rupees 4.0 lakh could be obtained. Considering the various parameters, the 80% ET level could be used to achieve higher yield and net returns from onion.